Method of making a semiconductor chip assembly with a copper/aluminum post/base heat spreader

• US 8,034,645 B2
• Filed: 11/30/2009
• Issued: 10/11/2011
• Est. Priority Date: 03/25/2008
• Status: Expired due to Fees

• Current Assignee: Bridge Semiconductor Corporation
• Original Assignee: Bridge Semiconductor Corporation
• Inventors: Lin, Charles W. C., Wang, Chia-Chung
• Primary Examiner(s): Lindsay, Jr.; Walter L
• Assistant Examiner(s): JUNGE, BRYAN R.
• Application Number:
  US12/626,941
• Publication Number:
  US 20100087020A1
• Time in Patent Office: 680 Days
• Field of Search: 438/25, 438/26, 438/118, 438/122, 257/707
• US Class Current: 438/26
• CPC Class Codes: H01L 21/486 Via connections through the substrate with or without pins
• CPC Class Codes: H01L 2224/32188 the layer connector connecting to a bonding area protruding from the surface of the item
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/85205 Ultrasonic bonding
• CPC Class Codes: H01L 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/49 of a plurality of wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01012 Magnesium [Mg]
• CPC Class Codes: H01L 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01087 Francium [Fr]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 33/483 : Containers
• CPC Class Codes: H01L 33/642 : characterized by the shape
• CPC Class Codes: H05K 1/0204 : using means for thermal conduction connection in the thickness direction of the substrate H05K1/0207 takes precedence
• CPC Class Codes: H05K 2201/09054 : Raised area or protrusion of metal substrate
• CPC Class Codes: H05K 2201/10106 : Light emitting diode [LED]
• CPC Class Codes: H05K 2203/0369 : Etching selective parts of a metal substrate through part of its thickness, e.g. using etch resist
• CPC Class Codes: H05K 3/0061 : onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20

Abstract

A method of making a semiconductor chip assembly includes providing a post and a base that include a copper surface layer and an aluminum core, mounting an adhesive on the base including inserting the post into an opening in the adhesive, mounting a conductive layer on the adhesive including aligning the post with an aperture in the conductive layer, then flowing the adhesive into and upward in a gap located in the aperture between the post and the conductive layer, solidifying the adhesive, then providing a conductive trace that includes a pad, a terminal and a selected portion of the conductive layer, mounting a semiconductor device on a heat spreader that includes the post and the base, electrically connecting the semiconductor device to the conductive trace and thermally connecting the semiconductor device to the heat spreader.

Claims

1. A method of making a semiconductor chip assembly, comprising:

providing a post, a base, an adhesive and a conductive layer, wherein

the post is adjacent to the base, extends above the base in an upward direction, extends into an opening in the adhesive and is aligned with an aperture in the conductive layer,

the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions,

the post and the base include a copper surface layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, and the aluminum core of the post extends above the copper surface layer of the base,

the adhesive is mounted on and extends above the base, is sandwiched between the base and the conductive layer and is non-solidified, and

the conductive layer is mounted on and extends above the adhesive;

then

flowing the adhesive into and upward in a gap located in the aperture between the post and the conductive layer;

solidifying the adhesive;

then

providing a conductive trace that includes a pad, a terminal and a selected portion of the conductive layer;

providing a heat spreader that includes the post and the base, wherein providing the heat spreader includes grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that includes the copper surface layer, excludes the aluminum core and faces in the upward direction;

mounting a semiconductor device on the heat spreader, wherein the semiconductor device overlaps the post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

2. The method of claim 1, wherein providing the post and the base includes:

providing an aluminum plate;

forming an etch mask on the aluminum plate that selectively exposes the aluminum plate;

etching the aluminum plate in a pattern defined by the etch mask, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate;

then

removing the etch mask, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess; and

then

depositing the copper surface layer over the aluminum core.

3. The method of claim 1, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

4. The method of claim 1, wherein flowing the adhesive includes filling the gap with the adhesive.

5. The method of claim 1, wherein mounting the conductive layer includes mounting the conductive layer alone on the adhesive.

6. The method of claim 1, wherein:

mounting the conductive layer includes mounting the conductive layer and a carrier on the adhesive, wherein the carrier is attached to and overlaps the conductive layer and the conductive layer contacts the adhesive and is sandwiched between the adhesive and the carrier;

then

solidifying the adhesive;

then

removing the carrier; and

then

providing the conductive trace.

7. The method of claim 1, wherein providing the pad includes removing selected portions of the conductive layer after solidifying the adhesive.

8. The method of claim 1, wherein providing the heat spreader includes providing a cap that extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the post and that overlaps and is adjacent to the adhesive after grinding the post, the adhesive and the conductive layer and before mounting the semiconductor device.

9. The method of claim 1, wherein mounting the semiconductor device includes providing a first solder joint between the semiconductor device and the pad and a second solder joint between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing the first solder joint between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the semiconductor device and the heat spreader.

10. The method of claim 1, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

11. A method of making a semiconductor chip assembly, comprising:

providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, the post and the base include a copper surface layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, and the aluminum core of the post extends above the copper surface layer of the base, and providing the post and the base includes;

providing an aluminum plate;

forming an etch mask on the aluminum plate that selectively exposes the aluminum plate;

etching the aluminum plate in a pattern defined by the etch mask, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate;

then

removing the etch mask, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess;

then

electrolessly plating a nickel buffer layer on the aluminum core;

electrolessly plating a first copper layer on the nickel buffer layer; and

electroplating a second copper layer on the first copper layer, wherein the copper surface layer includes the first and second copper layers;

providing an adhesive, wherein an opening extends through the adhesive;

providing a conductive layer, wherein an aperture extends through the conductive layer;

mounting the adhesive on the base, including inserting the post into the opening, wherein the adhesive extends above the base and the post extends through the opening;

mounting the conductive layer on the adhesive, including aligning the post with the aperture, wherein the conductive layer extends above the adhesive and the adhesive is sandwiched between the base and the conductive layer and is non-solidified;

then

applying heat to melt the adhesive;

moving the base and the conductive layer towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the conductive layer, wherein the pressure forces the molten adhesive to flow into and upward in a gap located in the aperture between the post and the conductive layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the conductive layer;

then

providing a conductive trace that includes a pad and a terminal, wherein the conductive trace includes selected portions of the conductive layer and an electrically conductive path is between the pad and the terminal;

mounting a semiconductor device on a heat spreader that includes the post and the base, wherein the semiconductor device overlaps the post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

12. The method of claim 11, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

13. The method of claim 11, wherein providing the pad and the terminal includes removing selected portions of the conductive layer using a second etch mask that defines the pad and the terminal after solidifying the adhesive.

14. The method of claim 11, wherein providing the pad includes removing selected portions of the conductive layer using a second etch mask that defines the pad after solidifying the adhesive, and providing the terminal includes removing selected portions of the base using a third etch mask that defines the terminal after solidifying the adhesive.

15. The method of claim 11, wherein providing the heat spreader includes providing a cap that extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the post and that overlaps and is adjacent to the adhesive using a second etch mask after solidifying the adhesive and before mounting the semiconductor device.

16. A method of making a semiconductor chip assembly, comprising:

providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, the post and the base include a copper surface layer, a nickel buffer layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, the aluminum core of the post extends above the copper surface layer of the base and the nickel buffer layer contacts and is sandwiched between and separates the copper surface layer and the aluminum core;

providing an adhesive, wherein an opening extends through the adhesive;

providing a conductive layer, wherein an aperture extends through the conductive layer;

mounting the adhesive on the base, including inserting the post through the opening, wherein the adhesive extends above the base and the post extends through the opening;

mounting the conductive layer alone on the adhesive, including inserting the post into the aperture, wherein the conductive layer extends above the adhesive, the post extends through the opening into the aperture, the adhesive is sandwiched between the base and the first conductive layer and is non-solidified, and a gap is located in the aperture between the post and the conductive layer;

then

applying heat to melt the adhesive;

moving the base and the conductive layer towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the conductive layer, wherein the pressure forces the molten adhesive to flow into and upward in the gap;

applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the conductive layer;

then

grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that includes the copper surface layer, excludes the nickel buffer layer and the aluminum core and faces in the upward direction;

then

providing a pad, a terminal and a routing line that include selected portions of the conductive layer, including removing selected portions of the conductive layer, wherein the pad, the terminal and the routing line include selected portions of the conductive layer and an electrically conductive path between the pad and the terminal includes the routing line;

mounting a semiconductor device on a heat spreader that includes the post and the base, wherein the semiconductor device overlaps the post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

17. The method of claim 16, wherein providing the post and the base includes:

providing an aluminum plate;

forming an etch mask on the aluminum plate that selectively exposes the aluminum plate;

etching the aluminum plate in a pattern defined by the etch mask, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate;

then

removing the etch mask, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess;

then

electrolessly plating a nickel buffer layer on the aluminum core;

electrolessly plating a first copper layer on the nickel buffer layer; and

electroplating a second copper layer on the first copper layer, wherein the copper surface layer includes the first and second copper layers.

18. The method of claim 16, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

19. The method of claim 16, wherein mounting the semiconductor device includes mounting an LED package that includes an LED chip on the pad using a first solder joint and on the heat spreader using a second solder joint, electrically connecting the semiconductor device includes providing the first solder joint between the LED package and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the LED package and the heat spreader.

20. The method of claim 16, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

21. A method of making a semiconductor chip assembly, comprising:

providing a post, a base, an adhesive and a substrate, wherein

the substrate includes a conductive layer and a dielectric layer,

the post is adjacent to the base, extends above the base in an upward direction, extends through an opening in the adhesive and extends into an aperture in the substrate,

the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions,

the post and the base include a copper surface layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, and the aluminum core of the post extends above the copper surface layer of the base,

the adhesive is mounted on and extends above the base, is sandwiched between the base and the substrate and is non-solidified,

the substrate is mounted on and extends above the adhesive, and the conductive layer extends above the dielectric layer, and

a gap is located in the aperture between the post and the substrate;

then

flowing the adhesive into and upward in the gap;

solidifying the adhesive;

then

providing a heat spreader that includes the post and the base, wherein providing the heat spreader includes grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that includes the copper surface layer, excludes the aluminum core and faces in the upward direction;

mounting a semiconductor device on the heat spreader, wherein the semiconductor device overlaps the post, a conductive trace includes a pad, a terminal and a selected portion of the conductive layer and the pad is electrically connected to the terminal;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

22. The method of claim 21, wherein providing the post and the base includes:

providing an aluminum plate;

forming an etch mask on the aluminum plate that selectively exposes the aluminum plate;

etching the aluminum plate in a pattern defined by the etch mask, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate;

then

removing the etch mask, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess; and

then

depositing the copper surface layer over the aluminum core.

23. The method of claim 21, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the substrate; and

solidifying the adhesive includes curing the uncured epoxy.

24. The method of claim 21, wherein flowing the adhesive includes filling the gap with the adhesive.

25. The method of claim 21, wherein providing the pad includes removing selected portions of the conductive layer after solidifying the adhesive.

26. The method of claim 21, wherein providing the pad and the terminal includes removing selected portions of the conductive layer after solidifying the adhesive.

27. The method of claim 21, wherein providing the terminal includes removing selected portions of the base after solidifying the adhesive.

28. The method of claim 21, wherein providing the heat spreader includes providing a cap that extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the post and that overlaps and is adjacent to the adhesive after grinding the post, the adhesive and the conductive layer and before mounting the semiconductor device.

29. The method of claim 21, wherein mounting the semiconductor device includes providing a first solder joint between the semiconductor device and the pad and a second solder joint between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing the first solder joint between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the semiconductor device and the heat spreader.

30. The method of claim 21, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

31. A method of making a semiconductor chip assembly, comprising:

providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, the post and the base include a copper surface layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, and the aluminum core of the post extends above the copper surface layer of the base, and providing the post and the base includes;

providing an aluminum plate;

forming an etch mask on the aluminum plate that selectively exposes the aluminum plate;

etching the aluminum plate in a pattern defined by the etch mask, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate;

then

removing the etch mask, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess;

then

electrolessly plating a nickel buffer layer on the aluminum core;

electrolessly plating a first copper layer on the nickel buffer layer; and

electroplating a second copper layer on the first copper layer, wherein the copper surface layer includes the first and second copper layers;

providing an adhesive, wherein an opening extends through the adhesive;

providing a substrate that includes a conductive layer and a dielectric layer, wherein an aperture extends through the substrate;

mounting the adhesive on the base, including inserting the post through the opening, wherein the adhesive extends above the base and the post extends through the opening;

mounting the substrate on the adhesive, including inserting the post into the aperture, wherein the substrate extends above the adhesive, the conductive layer extends above the dielectric layer, the post extends through the opening into the aperture, the adhesive is sandwiched between the base and the substrate and is non-solidified, and a gap is located in the aperture between the post and the substrate;

then

applying heat to melt the adhesive;

moving the base and the substrate towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the substrate, wherein the pressure forces the molten adhesive to flow into and upward in the gap and the post and the molten adhesive extend above the dielectric layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the substrate;

then

mounting a semiconductor device on a heat spreader that includes the post and the base, wherein the semiconductor device overlaps the post, a conductive trace includes a pad, a terminal and a selected portion of the conductive layer and the pad is electrically connected to the terminal;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

32. The method of claim 31, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the substrate; and

solidifying the adhesive includes curing the uncured epoxy.

33. The method of claim 31, wherein providing the pad and the terminal includes removing selected portions of the conductive layer using a second etch mask that defines the pad and the terminal after solidifying the adhesive.

34. The method of claim 31, wherein providing the pad includes removing selected portions of the conductive layer using a second etch mask that defines the pad after solidifying the adhesive, and providing the terminal includes removing selected portions of the base using a third etch mask that defines the terminal after solidifying the adhesive.

35. The method of claim 31, wherein providing the heat spreader includes providing a cap that extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the post and that overlaps and is adjacent to the adhesive using a second etch mask after solidifying the adhesive and before mounting the semiconductor device.

36. A method of making a semiconductor chip assembly, comprising:

providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, the post and the base include a copper surface layer, a nickel buffer layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, the aluminum core of the post extends above the copper surface layer of the base and the nickel buffer layer contacts and is sandwiched between and separates the copper surface layer and the aluminum core;

providing an adhesive, wherein an opening extends through the adhesive;

providing a substrate that includes a first conductive layer and a dielectric layer, wherein an aperture extends through the substrate;

mounting the adhesive on the base, including inserting the post through the opening, wherein the adhesive extends above the base and the post extends through the opening;

mounting the substrate on the adhesive, including inserting the post into the aperture, wherein the substrate extends above the adhesive, the first conductive layer extends above the dielectric layer, the post extends through the opening into the aperture, the adhesive is sandwiched between the base and the substrate and is non-solidified, and a gap is located in the aperture between the post and the substrate;

then

applying heat to melt the adhesive;

moving the base and the substrate towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the substrate, wherein the pressure forces the molten adhesive to flow into and upward in the gap and the post and the molten adhesive extend above the dielectric layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the substrate;

then

grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that includes the copper surface layer, excludes the nickel buffer layer and the aluminum core and faces in the upward direction;

then

providing a pad and a terminal that include selected portions of the conductive layer, including removing selected portions of the conductive layer;

mounting a semiconductor device on a heat spreader that includes the post and the base, wherein the semiconductor device overlaps the post and the pad is electrically connected to the terminal;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

37. The method of claim 36, wherein providing the post and the base includes:

providing an aluminum plate;

forming an etch mask on the aluminum plate that selectively exposes the aluminum plate;

etching the aluminum plate in a pattern defined by the etch mask, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate;

then

removing the etch mask, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess;

then

electrolessly plating a nickel buffer layer on the aluminum core;

electrolessly plating a first copper layer on the nickel buffer layer; and

electroplating a second copper layer on the first copper layer, wherein the copper surface layer includes the first and second copper layers.

38. The method of claim 36, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the substrate; and

solidifying the adhesive includes curing the uncured epoxy.

39. The method of claim 36, wherein mounting the semiconductor device includes mounting an LED package that includes an LED chip on the pad using a first solder joint and on the heat spreader using a second solder joint, electrically connecting the semiconductor device includes providing the first solder joint between the LED package and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the LED package and the heat spreader.

40. The method of claim 36, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

41. A method of making a semiconductor chip assembly, comprising:

providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, the post and the base include a copper surface layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, and the aluminum core of the post extends above the copper surface layer of the base;

providing an adhesive, wherein an opening extends through the adhesive;

providing a conductive layer, wherein an aperture extends through the conductive layer;

mounting the adhesive on the base, including inserting the post into the opening, wherein the adhesive extends above the base and the post extends through the opening;

mounting the conductive layer on the adhesive, including aligning the post with the aperture, wherein the conductive layer extends above the adhesive and the adhesive is sandwiched between the base and the conductive layer and is non-solidified;

then

applying heat to melt the adhesive;

moving the base and the conductive layer towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the conductive layer, wherein the pressure forces the molten adhesive to flow into and upward in a gap located in the aperture between the post and the conductive layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the conductive layer;

then

providing a conductive trace that includes a pad and a terminal, wherein the conductive trace includes selected portions of the conductive layer and an electrically conductive path is between the pad and the terminal;

providing a heat spreader that includes the post and the base;

providing the pad and the heat spreader including;

grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that includes the copper surface layer, excludes the aluminum core and faces in the upward direction; and

then

removing selected portions of the conductive layer using an etch mask that defines the pad;

mounting a semiconductor device on the heat spreader, wherein the semiconductor device overlaps the post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

42. The method of claim 41, wherein providing the post and the base includes:

providing an aluminum plate;

etching the aluminum plate, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess;

then

electrolessly plating a nickel buffer layer on the aluminum core;

electrolessly plating a first copper layer on the nickel buffer layer; and

electroplating a second copper layer on the first copper layer, wherein the copper surface layer includes the first and second copper layers.

43. The method of claim 41, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

44. The method of claim 41, wherein mounting the conductive layer includes mounting the conductive layer alone on the adhesive.

45. The method of claim 41, including grinding the adhesive without grinding the post.

46. A method of making a semiconductor chip assembly, comprising:

providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, the post and the base include a copper surface layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, and the aluminum core of the post extends above the copper surface layer of the base;

providing an adhesive, wherein an opening extends through the adhesive;

providing a conductive layer, wherein an aperture extends through the conductive layer;

mounting the adhesive on the base, including inserting the post into the opening, wherein the adhesive extends above the base and the post extends through the opening;

mounting the conductive layer on the adhesive, including aligning the post with the aperture, wherein the conductive layer extends above the adhesive and the adhesive is sandwiched between the base and the conductive layer and is non-solidified;

then

applying heat to melt the adhesive;

moving the base and the conductive layer towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the conductive layer, wherein the pressure forces the molten adhesive to flow into and upward in a gap located in the aperture between the post and the conductive layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the conductive layer;

then

providing a conductive trace that includes a pad and a terminal, wherein the conductive trace includes selected portions of the conductive layer and an electrically conductive path is between the pad and the terminal;

providing a heat spreader that includes the post and the base;

providing the pad and the heat spreader including;

grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that includes the copper surface layer, excludes the aluminum core and faces in the upward direction;

then

depositing a second conductive layer on the post, the adhesive and the conductive layer;

forming an etch mask on the second conductive layer;

etching the conductive layers using the etch mask to define the pad;

etching the second conductive layer using the etch mask to define a cap that extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the post and that overlaps and is adjacent to the adhesive, wherein the heat spreader includes the cap; and

then

removing the etch mask;

mounting a semiconductor device on the cap, wherein the semiconductor device overlaps the post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the cap, thereby thermally connecting the semiconductor device to the base.

47. The method of claim 46, wherein providing the post and the base includes:

providing an aluminum plate;

etching the aluminum plate, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess;

then

electrolessly plating a nickel buffer layer on the aluminum core;

electrolessly plating a first copper layer on the nickel buffer layer; and

electroplating a second copper layer on the first copper layer, wherein the copper surface layer includes the first and second copper layers.

48. The method of claim 46, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

49. The method of claim 46, wherein mounting the conductive layer includes mounting the conductive layer alone on the adhesive.

50. The method of claim 46, including grinding the adhesive without grinding the post.

51. A method of making a semiconductor chip assembly, comprising:

providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, the post and the base include a copper surface layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, and the aluminum core of the post extends above the copper surface layer of the base;

providing an adhesive, wherein an opening extends through the adhesive;

providing a substrate that includes a conductive layer and a dielectric layer, wherein an aperture extends through the substrate;

mounting the adhesive on the base, including inserting the post through the opening, wherein the adhesive extends above the base and the post extends through the opening;

mounting the substrate on the adhesive, including inserting the post into the aperture, wherein the substrate extends above the adhesive, the conductive layer extends above the dielectric layer, the post extends through the opening into the aperture, the adhesive is sandwiched between the base and the substrate and is non-solidified, and a gap is located in the aperture between the post and the substrate;

then

applying heat to melt the adhesive;

moving the base and the substrate towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the substrate, wherein the pressure forces the molten adhesive to flow into and upward in the gap and the post and the molten adhesive extend above the dielectric layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the substrate;

then

providing a conductive trace that includes a pad, a terminal and a selected portion of the conductive layer, wherein the pad is electrically connected to the terminal;

providing a heat spreader that includes the post and the base;

providing the pad and the heat spreader including;

grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that includes the copper surface layer, excludes the aluminum core and faces in the upward direction; and

then

removing selected portions of the conductive layer using an etch mask that defines the pad;

mounting a semiconductor device on the heat spreader, wherein the semiconductor device overlaps the post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

52. The method of claim 51, wherein providing the post and the base includes:

providing an aluminum plate;

etching the aluminum plate, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess;

then

electrolessly plating a nickel buffer layer on the aluminum core;

electrolessly plating a first copper layer on the nickel buffer layer; and

electroplating a second copper layer on the first copper layer, wherein the copper surface layer includes the first and second copper layers.

53. The method of claim 51, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

54. The method of claim 51, including grinding the adhesive without grinding the post.

55. The method of claim 51, including using the etch mask to define the terminal.

56. A method of making a semiconductor chip assembly, comprising:

providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, the post and the base include a copper surface layer and an aluminum core, the copper surface layer conformally coats and extends above the aluminum core, and the aluminum core of the post extends above the copper surface layer of the base;

providing an adhesive, wherein an opening extends through the adhesive;

providing a substrate that includes a conductive layer and a dielectric layer, wherein an aperture extends through the substrate;

mounting the adhesive on the base, including inserting the post through the opening, wherein the adhesive extends above the base and the post extends through the opening;

mounting the substrate on the adhesive, including inserting the post into the aperture, wherein the substrate extends above the adhesive, the conductive layer extends above the dielectric layer, the post extends through the opening into the aperture, the adhesive is sandwiched between the base and the substrate and is non-solidified, and a gap is located in the aperture between the post and the substrate;

then

applying heat to melt the adhesive;

moving the base and the substrate towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the substrate, wherein the pressure forces the molten adhesive to flow into and upward in the gap and the post and the molten adhesive extend above the dielectric layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the substrate;

then

providing a conductive trace that includes a pad, a terminal and a selected portion of the conductive layer, wherein the pad is electrically connected to the terminal;

providing a heat spreader that includes the post and the base;

providing the pad and the heat spreader including;

grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that includes the copper surface layer, excludes the aluminum core and faces in the upward direction;

then

depositing a second conductive layer on the post, the adhesive and the conductive layer;

forming an etch mask on the second conductive layer;

etching the conductive layers using the etch mask to define the pad;

etching the second conductive layer using the etch mask to define a cap that extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the post and that overlaps and is adjacent to the adhesive, wherein the heat spreader includes the cap; and

then

removing the etch mask;

mounting a semiconductor device on the cap, wherein the semiconductor device overlaps the post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the cap, thereby thermally connecting the semiconductor device to the base.

57. The method of claim 56, wherein providing the post and the base includes:

providing an aluminum plate;

etching the aluminum plate, thereby forming a recess in the aluminum plate that extends into but not through the aluminum plate, wherein the aluminum core of the post is an unetched portion of the aluminum plate that is laterally surrounded by the recess, and the aluminum core of the base is an unetched portion of the aluminum plate below the recess;

then

electrolessly plating a nickel buffer layer on the aluminum core;

electrolessly plating a first copper layer on the nickel buffer layer; and

electroplating a second copper layer on the first copper layer, wherein the copper surface layer includes the first and second copper layers.

58. The method of claim 56, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

59. The method of claim 56, including grinding the adhesive without grinding the post.

60. The method of claim 56, including etching the conductive layers using the etch mask to define the terminal.